Reviewers for minor fix needed - D43146


in rL324593 [1], a workaround was implemented to fix an infinite
recursion with the c?zdi2 builtins. Unfortunately, the change in
[1] is not 100% correct as - for example - assumes that a 64-Bit
SPARC environment always defines the macro "__sparc64__" which is
not correct for Linux but for BSD (and Solaris?) systems only.

The more portable approach is to check for __sparc__ and __arch64__
(not to be confused with __aarch64__). The change to fix this can
be found in [2].

Could someone review and merge it so the workaround doesn't have to
be patched locally anymore to workaround the problem on Linux/sparc64?